CN104564489B - The marine tidal-current energy wheel hub structure of passive Power Limitation - Google Patents

Abstract

The tidal current energy hub structure with passive power limitation includes a hub shell, a guide rod is arranged inside the hub shell, a pre-tightening nut is screwed on the left end of the guide rod, and a ring rack is set on the right end of the guide rod, and the ring rack can slide along the guide rod. There is a spring between the pre-tightening nut and the ring rack; the ring rack is meshed with a plurality of gears in the circumferential direction, and the upper end of each gear is fixedly connected to the flange base for installing the blade; the upper edge of the hub shell There are multiple slots for the gear to pass through in the circumferential direction, and the middle part of the gear is fixed with a rotating shaft, which is rotatably installed on the support hole of the hub shell; when the tidal flow velocity is lower than the rated flow velocity, the blade is perpendicular to the hub shell The axis of the shaft does not incline. When the tidal flow velocity is greater than the rated flow velocity, the blades tilt to the right along the tidal flow direction, and the gear pushes the ring rack to move to the left on the guide rod. Advantages: When the tidal current flow rate is greater than the rated flow rate, the power and load of the tidal current energy generating set can be limited to protect the generator of the tidal current energy generating set.

Description

Tidal energy hub structure with passive power limitation

technical field

The invention belongs to the field of tidal current energy generation, and in particular relates to a tidal current energy hub structure.

Background technique

Under the background that the country vigorously advocates the development of renewable energy, tidal current energy technology and industry are developing rapidly. Tidal current energy has high energy density and strong predictability, and it can be predicted that it will occupy an important position in the future energy structure. Since the tidal current energy generating set operates in seawater, the conditions are extremely harsh, so the reliability of the tidal current energy generating set is the most important thing in the design of the whole machine. When the flow rate of the tidal current exceeds the design flow rate of the tidal current energy generating set, it is necessary to limit the power of the tidal current energy generating set to protect the generator of the tidal current energy generating set, which will also reduce the overall load of the tidal current energy generating set. In this way, Improve the reliability of tidal current energy generating set operation.

Existing methods for power limitation of tidal current energy generators include passive stall control and active pitch control, both of which essentially use the stall characteristics of the blades. The difference is that the former is passive stall, and the latter is by changing the pitch angle of the blade Active stall. For passive stall blades, when the tidal flow velocity exceeds the rated flow velocity, the energy capture efficiency of the blade will drop sharply. In order to make the blade passively stall, even when the tidal flow velocity is lower than the rated flow velocity, the energy capture efficiency of the blade will be sacrificed. For blades with active pitch control, when the current flow velocity is greater than the rated flow velocity, the blades are actively brought into a stall state by changing the pitch angle of the blades. The blades controlled in this way do not need to compromise on energy capture efficiency, but it A set of complex pitch-variable mechanism and its control method are required to be matched with it, which will affect the reliability of the tidal current energy generating set in underwater operation to a certain extent.

Contents of the invention

The invention aims at the deficiencies in the prior art, and provides a tidal energy hub structure without sacrificing the energy capture efficiency of the blades, without complex pitch adjustment mechanism, and with high reliability of underwater operation and limited passive power.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

The tidal current energy hub structure with passive power limitation includes a hub shell. A guide rod is arranged inside the hub shell. One end of the guide rod is against the left end of the hub shell, and the other end of the guide rod is against the right end of the hub shell. The left end is screwed with a pre-tightening nut, and the right end of the guide rod is set with a ring rack, which can slide along the guide rod. There is a spring between the pre-tightening nut and the ring rack, and the spring set is always in a compressed state on the guide rod. ; A plurality of gears are meshed with the annular rack along the circumferential direction, and the upper end surface of each gear is a plane and is fixedly connected with a flange base for fixing the blade, and a blade is fixedly installed on each flange base;

The hub shell is provided with a plurality of slots along the circumference for the gears to pass through. The thickness of the slots is suitable for the gears. There is a supporting hole on the part, and the rotating shaft is rotatably installed on the supporting hole; when the flow rate is lower than the rated flow rate, the ring rack is pressed against the right end of the hub shell under the action of the spring preload, and the blade is perpendicular to the hub shell The axis of the body does not incline. When the tidal flow velocity is greater than the rated velocity, the blades will incline to the right along the tidal flow direction, and the vanes will drive the flange base and the gears to rotate to the right along the supporting holes, and the gears will push the ring rack to go against the tidal current on the guide rod. The flow direction moves to the left; the lower end of each blade has a flange, and the flange is provided with a circle of first through holes, and the flange base is provided with a circle of second through holes matched with the first through holes, and the bolts pass through the first through holes. One through hole and the second through hole, the other end of the bolt is fixedly connected with the nut, so as to realize the fixed installation of the blade on the flange base;

The pre-tightening force of the spring is adjusted by the pre-tightening nut. Define the pre-tightening amount of the spring as S, the stiffness of the spring as K, the force arm from the ring rack to the rotating shaft as L, and the bending moment on a single blade at the rated flow rate as M, the number of blades is N, then the preload of the spring The unit of S is meter. Under the action of the spring preload, when the tidal flow velocity is lower than the rated flow velocity, the blade cannot push the guide rod to move, so the blade is not inclined perpendicular to the axis of the hub shell.

Further, three gears mesh with the annular rack along the circumferential direction, and the three gears are arranged at equal intervals of 120 degrees, and the hub shell is provided with slots along the circumferential direction for each gear to pass through.

Further, the hub shell includes a hub main body and a hub end cover, the hub main body and the hub end cover are detachably fixedly connected, one end of the guide rod is against the left end of the hub main body, and the other end of the guide rod is connected to the hub end cover. The right ends are offset, and the slot is opened between the hub main body and the hub end cover.

Further, the outer ring of the right end of the hub main body is provided with a first fixed disk, the outer ring of the left end of the hub end cover is provided with a second fixed disk, and the first fixed disk and the second fixed disk are correspondingly provided with fixing holes , the bolt passes through the fixing hole, and the other end of the bolt is fixedly connected with the nut.

Preferably, a guide is provided between the guide rod and the ring rack, and the guide is a guide groove provided on the guide rod and a raised bar provided on the ring rack to cooperate with the guide groove, or, The guide member is a guide bar arranged on the guide rod and a groove arranged on the ring rack to cooperate with the guide bar.

As an optional solution, two gears are meshed with the annular rack along the circumferential direction, and the two gears are arranged at equal intervals of 180 degrees, and the hub shell is provided with slots for each gear to protrude along the circumferential direction.

As an alternative solution, more than three gears are meshed with the ring gear along the circumferential direction, and the gears are arranged at equal intervals, and the hub shell is provided with slots for each gear to protrude along the circumferential direction .

The technical idea of the present invention is: set the pre-tightening force of the spring to be equal to the thrust of the ring rack on the spring at the rated flow rate. The force is equal to the thrust of the ring rack on the spring at the rated flow rate. The tidal current energy cannot push the blades to rotate. When the tilt occurs, the working area of the blade is the largest; when the current flow velocity is greater than the rated flow velocity, the load on the blade is greater than the rated load, and the blade will tilt to the right along the flow direction, driving the flange base and the gear to rotate to the right along the support hole, Thus, the ring rack is pushed to move to the left against the current flow on the guide rod, and the spring force and the load on the blades reach a new balance. Due to the inclination of the blades, the working area of the blades is reduced, the rotational speed at which the tidal current energy drives the blades to generate electricity is reduced, and the power and load of the tidal current energy generating set are also correspondingly reduced, which realizes the protection of the generator of the tidal current energy generating set.

As mentioned above, the tidal current energy hub structure of the present invention can passively limit the power of the tidal current energy generating set by tilting the blades. Changing the screw position of the pre-tightening nut on the guide rod can adjust the pre-tightening force of the spring, so as to adapt to the rated thrust of the ring rack on the spring under different rated flow rates. The ring rack meshes with multiple gears to realize the multi-blade synchronously driving the ring rack to move and the multi-blade rotation to generate electricity.

The tidal current energy generating set includes the nacelle, the tower supporting the nacelle, and the tidal energy hub structure that drives the main shaft in the nacelle to rotate. The hub shell of the tidal current energy hub structure is fixedly connected with the main shaft of the nacelle, and the tidal current can push the hub in a direction perpendicular to the gear. Multiple blades on the housing rotate, the blades drive the hub housing to rotate, and the hub housing drives the main shaft of the nacelle to rotate to generate electricity for the generator in the nacelle. Viewed along the flow direction of the tidal current, the tidal energy hub structure is arranged in front of the nacelle and the tower, and the blades are inclined along the direction of the tidal flow, that is, the blades are tilted away from the tower, so the tip of the blade will not interfere with the tower.

The beneficial effects of the present invention are: when the tidal flow velocity is greater than the rated velocity, the blades are tilted to limit the power and load of the tidal current energy generating set to protect the generator of the tidal energy generating set; when the tidal current velocity is at or below the rated velocity, the blades are vertically The straight arrangement does not incline, so the blades will not sacrifice their energy capture efficiency when the rated flow velocity is below the rated flow velocity; compared with the way of variable pitch, the hub structure of the present invention does not require a complicated pitch control mechanism, and the structure is simpler. There is no need for additional pitch control, which ensures the reliability of underwater operation.

Description of drawings

Fig. 1 is a matching diagram of an annular rack and a gear in Embodiment 1 of the present invention.

Fig. 2 is a diagram of the non-tilted state of the blades of the tidal energy hub structure according to Embodiment 1 of the present invention.

Fig. 3 is a diagram showing the tilted state of the blades of the tidal energy hub structure according to Embodiment 1 of the present invention.

Fig. 4 is a structural diagram of blades assembled on the tidal energy hub structure according to Embodiment 1 of the present invention.

Fig. 5 is a schematic structural diagram of a tidal current energy generating set according to Embodiment 1 of the present invention.

detailed description

Below in conjunction with accompanying drawing and embodiment the present invention is described in further detail:

Embodiment one

Refer to Figure 1-5: The tidal current energy hub structure with passive power limitation, including the hub shell 1, the guide rod 2 is arranged inside the hub shell 1, one end of the guide rod 2 is offset against the left end of the hub shell 1, and the guide rod 2 The other end is against the right end of the hub shell 1, the left end of the guide rod 2 is screwed with a pre-tightening nut 3, the right end of the guide rod 2 is fitted with a ring rack 4, the ring rack 4 can slide along the guide rod 2, and the pre-tightening nut 3 and the ring rack 4, there is a spring 5, and the spring 5 is set on the guide rod 2 and is always in a compressed state; the ring rack 4 is meshed with a plurality of gears 6 along the circumferential direction, and the upper end surface of each gear 6 is It is plane and fixedly connected with a flange base 8 for fixing the blade 7, and a blade 7 is fixedly installed on each flange base 8; the lower end of each blade 7 has a flange 71, and the flange 71 is provided with a circle of first pass hole, the flange base 8 is provided with a circle of second through holes 81 matching with the first through holes, the bolt passes through the first through hole and the second through hole 81, and the other end of the bolt is fixedly connected with the nut, so that Realize the fixed installation of the blade on the flange base 8;

The hub shell 1 is provided with a plurality of slots 9 along the circumference for the gear 6 to pass through, each slot 9 allows a gear 6 to protrude, the thickness of the slot 9 is adapted to the gear 6, and the gear 6 The middle part is fixed with a rotating shaft 10, and the two sides of each slot 9 are fixed with a supporting member 11, and the supporting member 11 is provided with a supporting hole 12, and the rotating shaft 10 is rotatably pierced on the supporting hole 12; when the current flow rate is lower than the rated flow rate , the ring rack 4 is pushed against the right end of the hub shell 1 under the pre-tightening force of the spring 5, and the blade 7 is perpendicular to the axis of the hub shell 1 without inclination. When the current flow rate is greater than the rated flow rate, the blade 7 flows along the flow direction Tilting to the right, the blade 7 drives the flange base 8 and the gear 6 to rotate rightward along the supporting hole 12, and the gear 6 pushes the ring rack 4 to move to the left against the flow direction on the guide rod 2;

The pretightening force of the spring 5 is adjusted by the pretightening nut 3, and the pretightening amount of the spring 5 is defined as S, the stiffness of the spring 5 is K, the force arm from the ring rack 4 to the rotating shaft 10 is L, and a single blade at the rated flow rate 7 The bending moment is M, the number of blades is N, then the spring preload The unit of S is meter. Under the action of the preload of the spring 5, when the tidal flow velocity is lower than the rated flow velocity, the blade 7 cannot push the guide rod 2 to move, so the blade 7 is not inclined perpendicular to the axis of the hub shell 1 . The bending moment M experienced by a single blade at the rated flow rate can be obtained by CFD software for flow field analysis.

In this embodiment, three gears 6 are meshed with the annular rack 4 along the circumferential direction, and the three gears 6 are arranged at equal intervals of 120 degrees, and the hub shell 1 is provided with slots along the circumferential direction for each gear 6 to pass through. 9. Three gears 6 are meshed with the ring rack 4 in the circumferential direction, so that the three blades synchronously push the ring rack 4 to move when the blades are tilted. The gear 8 pushes the hub shell 1 to rotate to generate electricity through the slot 9 . Figures 1-3 only show a gear meshing with the ring rack and the flange base, the blades are not shown.

In this embodiment, the hub shell 1 includes a hub main body 13 and a hub end cover 14, the hub main body 13 and the hub end cover 14 are detachably fixedly connected, one end of the guide rod 2 abuts against the left end of the hub main body 13, The other end of the guide rod 2 abuts against the right end of the hub end cover 14 , and the slot 9 is provided between the hub main body 13 and the hub end cover 14 .

The outer ring of the right end of the hub main body 13 is provided with a first fixed disk, the outer ring of the left end of the hub end cover 14 is provided with a second fixed disk 15, and the first fixed disk and the second fixed disk 15 are correspondingly provided with The fixing hole 16 , the bolt passes through the fixing hole 16 , and the other end of the bolt is fixedly connected with the nut, so as to realize the detachable fixed connection between the hub main body 13 and the hub end cover 14 .

In this embodiment, a guide is provided between the guide rod 2 and the ring rack 4, and the guide is a guide bar arranged on the guide rod 2 and arranged on the ring rack 4 to cooperate with the guide bar. The groove, so as to realize the sliding of the ring rack 4 along the guide rod 2. The guide member can also be a guide groove arranged on the guide rod 2 and a protruding line arranged on the ring rack 4 to cooperate with the guide groove.

In the present invention, the ring rack 4 is arranged with straight teeth 41 along the circumferential direction of 360 degrees, so as to engage a plurality of gears 6 in the circumferential direction of the ring rack 4, so that the multi-blades 7 can synchronously push the ring rack 4 to move, and multiple The blades 7 rotate to generate electricity.

The principle of passive power limitation of the hub structure of the present invention: set the pretightening force of the spring 5 to be equal to the thrust force of the ring rack 4 on the spring 5 at the rated flow rate, when the current flow rate is lower than the rated flow rate, that is, the load on the blade 7 is less than the rated flow rate. When under load, since the pretightening force of the spring 5 is equal to the thrust of the ring rack 4 on the spring 5 at the rated flow rate, the tidal current energy cannot push the blade 7 to rotate, and the ring rack 4 bears against the hub shell under the pretightening force of the spring 5 1, at this time, the blade 7 is perpendicular to the axis of the hub shell 1 without inclination, and the working area of the blade 7 is the largest; when the tidal flow velocity is greater than the rated flow velocity, the load on the blade 7 is greater than the rated load, and the blade 7 will flow along the flow direction Tilting to the right, drives the flange base 8 and the gear 6 to turn right along the supporting hole, the gear 6 pushes the ring rack 4 to move to the left against the current flow on the guide rod 2, and the spring force is equal to the load on the blade 7. A new balance. Due to the inclination of the blades, the working area of the blades is reduced, the rotational speed at which the tidal current energy pushes the blades to generate electricity (the speed at which the blades push the hub shell to rotate) decreases, and the power and load of the tidal current energy generating set are also reduced accordingly, realizing the realization of the power flow Generator protection for generator sets.

The rotational speed at which the tidal current can push the blades to generate electricity is related to the working area of the blades 7. When the working area of the blades is large, the promotion of the tidal currents has a more effective area, and the rotational speed at which the tidal energy can push the blades to rotate and generate electricity is also large.

As mentioned above, the tidal current energy hub structure of the present invention can passively limit the power of the tidal current energy generating set by tilting the blades 7 . Changing the screwed position of the pre-tightening nut 3 at the left end of the guide rod 2 can adjust the pre-tightening force of the spring 5, so as to adapt to the rated thrust of the ring rack 4 on the spring 5 under different rated flow rates.

In Fig. 5, the tidal current energy generating set includes a tower 17, a nacelle 18, and a tidal energy hub structure that drives the main shaft 19 of the nacelle 18 to rotate. , the nacelle 18 is placed on the tower 17, there is a generator and a speed-up gearbox in the nacelle 18, the output shaft of the speed-up gearbox is connected to the generator, the input shaft of the speed-up gearbox is the main shaft 19 of the nacelle and the trend of the present invention The hub shell 1 of the hub structure is fixedly connected, and the blade 7 is installed on the hub shell 1. The blade 7 drives the hub shell 1 to rotate under the action of the tidal current energy, thereby driving the main shaft 19 of the nacelle to rotate, and the main shaft 19 drives the interior of the nacelle 18. generators generate electricity. The tidal energy hub structure of the present invention adopts a "downwind" arrangement, that is, viewed along the flow direction of the tidal current, the nacelle 18 and the tower 17 are behind, and the tidal energy hub structure is in front, so that when the blades are tilted, the blades 7 will fall The direction away from the tower 17 is to ensure that the blade tip will not interfere with the tower 17.

In the present invention, the current flow direction is shown by the arrow in FIG. 5, that is, the current flow direction is rightward along the axial direction of the hub shell 1. When the current flow velocity is the rated flow velocity, the blade 7 is not inclined perpendicular to the axial direction of the hub shell 1. At this time, the working area of the blade 7 is the largest, and the rotational speed at which the tidal current can push the blade 7 to generate electricity (the speed at which the blade pushes the hub shell to rotate) is the largest; The working area of 7 is reduced, the rotating speed of the blade 7 driven by tidal current energy is reduced, and the power and load of the tidal current energy generator set are reduced, so the power and load of the tidal current energy generator set are passively limited.

The tidal current energy hub structure of the present invention, when the tidal current flow velocity is greater than the rated flow velocity, the blades are tilted to limit the power and load of the tidal current energy generating set, which can protect the generator of the tidal current energy generating set from over-speed rotation; the tidal current flow velocity is between the rated flow velocity and the rated flow velocity When the blades are vertically arranged, there will be no inclination, and the rotating speed of the blades will not decrease, so the blades will not sacrifice their energy capture efficiency when the rated flow velocity is lower than the rated flow velocity; The hub structure does not require a complex pitch control mechanism, the structure is simpler, and no additional pitch control is required, which ensures the reliability of underwater operation.

The passive power limitation of the tidal current energy hub structure of the present invention is different from the passive stall control in the background art. In order to make the blades stall passively, the rotating speed of the blades will decrease even when the tidal flow velocity is lower than the rated flow velocity. That is, the energy capture efficiency of the blades will also be sacrificed. In the hub structure of the present invention, when the tidal flow velocity is less than or equal to the rated flow velocity, the vertical arrangement of the blades does not incline, that is, the working area of the blades is the largest. At rated flow rates, the energy capture efficiency of the blades is not sacrificed.

Embodiment two

The difference between this embodiment and Embodiment 1 is that two gears are meshed with the annular rack along the circumferential direction, and the two gears are arranged at equal intervals of 180 degrees. out of the slot. Other structures and implementations of this embodiment are the same as those of Embodiment 1.

Embodiment Three

The difference between this embodiment and Embodiment 1 is that more than three gears are meshed with the ring gear along the circumferential direction, and the gears are arranged at equal intervals, and the hub shell is provided with the gears extending along the circumference. out of the slot. Other structures and implementations of this embodiment are the same as those of Embodiment 1.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention within.

Claims (7)

1. the marine tidal-current energy wheel hub structure of passive Power Limitation, it is characterised in that: include hub shell, hub shell The internal guide rod that is provided with, one end of guide rod offsets with the left end of hub shell, the other end of guide rod and hub shell The right-hand member of body offsets, and the left end of guide rod is screwed with pre-load nut, and the right-hand member of guide rod is set with annular rack, annular Tooth bar can have spring along guide rod sliding between pre-load nut and annular rack, spring housing is contained on guide rod the beginning It is in compressive state eventually；Multiple gear, the upper surface of each gear circumferentially it is engaged with on described annular rack For plane and an affixed flange base being used for fixedly mounting blade, each flange base fixedly mounts one Individual blade；Each blade lower end has ring flange, and ring flange is provided with circle first through hole, at the bottom of described flange Being provided with a circle and the second through hole of the first through hole cooperation on seat, bolt passes the first through hole and the second through hole, The other end of bolt is fixing with nut to be connected, and realizes blade fixed installation on flange base with this；

Circumferentially arranged on described hub shell have multiple fluting passed for gear, the thickness of fluting and gear Adaptation, gear be fixedly arranged in the middle of rotating shaft, each fluting both sides be installed with supporting member, supporting member is provided with Support holes, rotating shaft is rotating to be located in support holes；When tidal current speed is less than nominal flow rate, annular tooth Bar withstands on the right-hand member of hub shell under the pretightning force effect of spring, and blade is perpendicular to the axis of hub shell not Run-off the straight, when tidal current speed is more than nominal flow rate, blade fair tide flows to tilt to the right, blade band Dynamic flange base and gear turn right along support holes, and gear promotes annular rack opposite tide on guide rod to flow to It is moved to the left；

The pretightning force of spring is regulated by pre-load nut, and the pretension amount of definition spring is S, and the rigidity of spring is K, Annular rack is L to the arm of force of described rotating shaft, and under nominal flow rate, the moment of flexure suffered by individual blade is M, blade Quantity is N, then the pretension amount of springS unit is rice, under the pretension amount effect of this spring, When tidal current speed is less than nominal flow rate, it is mobile that blade can not promote annular rack to produce, and therefore blade is vertical Axis not run-off the straight in hub shell.

2. the marine tidal-current energy wheel hub structure of passive Power Limitation as claimed in claim 1, it is characterised in that: institute State and on annular rack, be circumferentially engaged with three gears, three gears 120 degree of settings, hub shells at equal intervals The most circumferentially arranged have three flutings stretched out for gear, and the position of fluting should with gear mesh.

3. the marine tidal-current energy wheel hub structure of passive Power Limitation as claimed in claim 1 or 2, it is characterised in that: Described hub shell includes the detachable fixing company of hub body and wheel hub end housing, hub body and wheel hub end housing Connecing, one end of described guide rod offsets with the left end of hub body, the other end of guide rod and the right-hand member of wheel hub end housing Offseting, described fluting is opened between hub body and wheel hub end housing.

4. the marine tidal-current energy wheel hub structure of passive Power Limitation as claimed in claim 3, it is characterised in that: institute The outer of the right-hand member stating hub body is equipped with the first fixed disk, and the outer of the left end of wheel hub end housing is equipped with Being correspondingly arranged on fixing hole on two fixed disks, the first fixed disk and the second fixed disk, bolt passes fixing hole, The other end of bolt is fixing with nut to be connected.

5. the marine tidal-current energy wheel hub structure of passive Power Limitation as claimed in claim 1, it is characterised in that: institute State and between guide rod and annular rack, be provided with guide, described guide be the guide groove being arranged on guide rod and It is arranged on annular rack the raised line coordinated with described guide groove, or, described guide is for being arranged on guide rod Sliver and be arranged on annular rack the groove coordinated with described sliver.

6. the marine tidal-current energy wheel hub structure of passive Power Limitation as claimed in claim 1, it is characterised in that: institute State and on annular rack, be circumferentially engaged with two gears, two gears 180 degree of settings, hub shells at equal intervals The most circumferentially arranged have the fluting stretched out for each gear.

7. the marine tidal-current energy wheel hub structure of passive Power Limitation as claimed in claim 1, it is characterised in that: institute State and be circumferentially engaged with on annular rack more than three gears, arrange at equal intervals between each gear, hub shell Circumferentially arranged on body have the fluting stretched out for each gear.